Governing mechanism for elastic-fluid turbines.



W. KIESER. GOVERNING MECHANISM FOR ELASTIC FLUID TURBINES. APPLIOATIONFILED 00T.29, 1906.

1 .889 Patented May 17, 1910.

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ANDREW B, GRAHAM 00., Fumaumoclmwtns vyAsmNuwK, 11.

W. KIESER.

GOVERNING MECHANISM FOR ELASTIC FLUID TUBBINES.

APPLICATION FILED OUT-29,1906.

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ANDREW B GRAHAM 00. PNUTO-LITHOGRAPHERS, wAsmNmwN, n. c

W. KIESER.

GOVERNING MECHANISM FOR ELASTIC FLUID TURBINES.

APPLIGATION FILED 0GT.2Q, 1906.

y 0.. w m m vms w o. N mK Wm w m m m a Em m6 dol @wrn Witnesses ANDREWa, GRAHAM co., PHOTO-LITHOGHAPHERS, WASHINGTON, a

WALTER KIESER, OF BERLIN, GERMANY, ASSIGNOR TO GENERAL ELECTRIC COMPANY,

A CORPORATION OF NEW YORK.

GOVERNING MECHANISM FOR ELASTIC-FLUID TURBINE-S.

Specification of Letters Patent.

Application filed October 29, 1906.

Patented May 17, 1910. Serial No. 340,995.

To all whom it may concern:

Be it known that I, WALTER Krnsnn, a citizen of Switzerland, residing atBerlin, Germany, have invented certain new and useful Improvements inGoverning Mechanism for Elastic-Fluid Turbines, of which the followingis a specification.

The present invention relates to governing mechanisms for elastic fluidturbines, and has for its object to provide an improved governingmechanism which is simple and rugged in construction, and which willel'li ciently regulate the passage of motive fluid through the turbine.

For a fuller understanding of what I consider to be novel and myinvention, attention is directed to the accompanying descrip tion andclaims appended thereto.

In the accompanying drawings which illustrate one of the embodiments ofmy invention, Figure 1 is an end view of an elas tic fluid turbinefitted with my improved governing mechanism; Fig. 2 is a section throughthe governing valve and the hydraulio motor for actuating it; Fig. 3is adetail view, principally in section, of the pilot valve for controllingthe hydraulic mtor, and also of the adjustable governor opposingsprings, and Fig. 4 is a detail view of an improved form of mainthrottle valve.

1 represents the turbine which may be of any suitable construction. Asshown, it is of the Curtis type. Steam or other elastic fluid isadmitted to the bucket wheel by the sectionalized nozzle 2. I have shownthe nozzle sections as being of the expanding type, but it is to beunderstood that the invention is applicable to turbines havingnon-expanding nozzles, and also to turbines having discharging devicesof other forms. As shown, the nozzle sections are divided into groups,Fig. 2, each group receiving its motive fluid from a separate port. Inthe particular embodiment shown, ports 3, 4., 5 and 6 are provided. Theport 3 is arranged to supply motive fluidto three nozzle sections andthe remaining ports each to two nozzle sections, but the number can beincreased or decreased as desired. The ports 3 to 6 inclusivecommunicate with corresponding ports formed in the valve chest 7. Ports1 to 6 inclusive are opened or closed by manually actuated valves 8, ofwhich three are shown, but the number can be increased or decreased asdesired. These valves may be actuated by a detachable handle 9 or othermeans. In the operation of the turbine, these valves will be opened oneafter the other by the station attendant as the load increases, andclosed one after the other by the attendant as the load decreases. It isnot intended to open and close these valves for minor changes in load,but only for material changes, such as commonly occur from time to timeduring the day in the operation of steam plants supplying energy tolight ing, railway and power circuits. F or this reason the manuallyactuated valves will be referred to as secondary controlling orregulating devices. The primary controlling device comprises adouble-seated balanced throttle valve 10 mounted within the valve chestand attached to a rod 11. The latter is provided with a tail-pieceacting as a guide for the lower end, and an extension 13 on the upperend that is united with the piston of the hydraulic motor 14. Theportion ofthe rod 11 extending through the valve chest is slotted, andthe stems of the manually actuated valves Sextend through said slot. Theobject of slotting the rod and passing the valve stems through the slotis to reduce the size of the apparatus as a whole. Where the extension13 passes through the head of the valve chest, it is provided with anadjustable packing gland 15.

The motor 14 comprises a cylinder 16, a piston 17, an entrance port atthe upper end of the cylinder and an exhaust port at the lower end. Thepipes for admitting fluid, such as oil under pressure, to. the cylinder,are best shown in Fig. 1. The piston being directly connected to thethrottle valve through the parts 13 andll, it follows that as the pistonchanges its position, that of the throttle valve will be correspondinglychanged. When the piston is in the extreme upper position, as shown inFig. 2, the maximum amount of steam will flow from the supply conduit 18to the turbine, and intermediate positions of the piston and valve willadmit a correspondingly decreased amount of steam. When the piston is inits lowest position, the upper surface of the valve will engage the seat19, while the lower surface of the valve will engage the seat 20. .Theseats 19 and 20 are formed on the same member, and said member issecurely held between the valve chest and a flanged coupling 21. Byreason of this construction, only one set of bolts is required, andthese pass through the flanges of the chest and the coupling.

To the lower end of the flanged coupling is attached the casing 22 ofthe emergency valve mechanism, the latter including a valve 23 having ascrew-threaded stem 24. The valve is continually urged toward its seatby a compression spring 25 and is normally held open by a trigger 26which is under the control of a speed responsive device driven by theturbine. Then the speed of the machine exceeds a predetermined amount,the emergency governor, acting through the rod 27 and connected parts,releases the lock and permits the compression spring 25 to close thevalve. For the purpose of opening the valve, a beveled gear 30 issplined on an extension of the valve spindle. This gear meshes with apinion 32 carried by the upright spindle 33. At the top of the spindle,the handle 34 is provided for rotating the gears. Surrounding the valvestem is a nut 31 which is splined to prevent it from rotating with thevalve spindle, and is normally held against longitudinal movement by theemergency trigger 26. The construction of the emergency valve andcontrolling'mechanism therefor is not claimed herein, since it forms thesubject matter of a separate application, Serial No. 400345, filed,November 2, 1907. The means for opening and closing the emergency valveare inclosed in a suitable casing, which casing is attached to that ofthe emergency valve.

7 a The means for actuating the pilot valve of the hydraulic motor willnow be described.

Referring to Fig. 1, 35 represents a centrifugal governor of anyapproved type, that is driven by a vertical shaft 36, Fig. 3, from themain shaft of the turbine through suitable speed reducing gearing.Mounted on the low speed shaft 36 is a sliding collar 37, or'equivalentdevice, which is connected to the governor weights by levers 38 andlinks 39. Pivotally connected to the collar is a horizontal governorlever 40, which, for convenience, is made of two parallel membersconnected by bolts 41 and separated by space blocks 42, shown in dottedlines, Fig. 3. The right hand end of the lever is con nected to thepiston rod by the pivot 44, the arrangement of parts being such that,when the governor collar moves up or down, the

lever moves about the pivot 44 as a fulcrum.

Just as soon as the motor piston starts into operation, the fulcrum ofthe lever shifts from the pivot 44 to the pivot 43 carried by thegovernor collar 37.

Mounted on the end of the bracket 45, extending laterally from thecasing surrounding the low speed shaft, is a valve casing 46 containinga balanced piston relay or pilot valve 47, for controlling the hydraulicmotor. The upper end of the valve stem passes through a trunnion block48, and the latter is connected by the pivots 49 with the horizontalgovernor lever, so that the motion of the lever is transmitted to thepilot valve. Situated above and below the trunnion block and engagingtherewith are collars for transmitting motion from the gov ernor leverto the valve stem. This arrangement forms a part of a follow-upmechanism to restore the pilot valve to its normal position and preventsover-travel of the motor and throttle valve. Without such a device, thegoverning mechanism would tend to hunt, i. 6., the motor piston, andconsequently, the throttle valve would tend to move too far each timethe load changed to supply the exact amount of steam required for anygiven condition of load.

Mounted on the valve casing 46, and rising vertically therefrom, are twopillars 50 supporting at their upper end a plate 51 forming an abutmentfor the compression springs 52 and 53. The tension of these springs canbe adjusted by changing the vertical position of the plate 51 and thenut on the end of the valve stem and the nuts on the pillars. The objectof these springs is to form a cushioning device between the governorlever and the pilot valve. The valve casing is provided with anadmission port 54, shown in dotted lines, for high pressure fluid and anexhaust port 55. The heads of the piston valve are arranged to controlthe passage of fluid leading to the ports 56 and 57, the formercommunicating with the upper side of the piston and the latter with theunder side. The heads of the piston and the seats therefor are soarranged that there is little or no overlap. With the parts in theposition shown, the ports 56 and 57 are closed and the piston of themotor is therefore held between two bodies of incompressible fluid, onelocated above and the other below the piston. Assuming that'thc pistonvalve is raised, it will admit high-pressure fluid to the port 56 and tothe upper side of the piston; at the same time, the port 57 is uncoveredand placed in commui'iication with the exhaust 55. In order to fullybalance the pilot valve, a passage 58 is provided communicating with achamber into which the lower end of the valve projects at one end, andwith the exhaust 55 at the other.

From time to time, it becomes necessary, for various reasons andparticularly for cutting turbines into and out of service when arrangedto drive a common load, to vary the speed at which the turbine will run.In order to do this, I provide a means for changing the force opposingthe governor weights. In the present embodiment of my invention, this iscarried out by the following means: Located between the members of thehorizontal governor lever is a lever 60 that is connected to the pilotvalve stem on the right hand end by the pivots 49. To the left hand endof the lever is pivoted a rod 61. This rod is provided with a shoulderto receive the head 62 at its upper end, and a nut at its lower end,forming a seat for the head 68. Surrounding the rod 61 are twocompression springs 64 and 65 act ing in opposition to each other.Between these springs is located an adjustable abutment 66 comprising acylindrical member guided in its vertical movements by the walls of anenlargement in the bracket 45, and provided with a shoulder 67 betweenthe upper and lower springs. The abutment is provided with a lateralextension through which a screw-threaded spindle 68. extends. Rotatingthe hand wheel on the end of the spindle in one direction or the otherincreases the tension on one spring and decreases the tension on theother. In this manner either the upper or the lower spring can bearranged to have a greater or less tension. The lever 60 is supported atan intermediate point by a pivot supported by a vertical link 69, sothat any movement of the main horizontal lever either up or down fromthe central position will be opposed by one of the springs.

The action of my improved governing mechanism is as follows: Assumingthat the speed of the turbine increases due to a decrease in load orotherwise, the collar 37 will raise the left hand end of the lever 40about the pivot 44 as a fulcrum, and with it, the pilot valve 47. Thisopens the port 56 communicating with the top of the cylinder of thehydraulic motor, and the piston therein starts into motion in a downwarddirection. The pivot 43, Fig. 8, now becomes the fulcrum about which thelever moves, owingto the fact that the pivot 44 on the right hand end ofthe lever is connected to and moves with the motor piston. Depressingthe pivot 44 means that the pivots 49 and the pilot valve will also bedepressed, and just as soon as this downward movement suffices to movethe pilot valve over the ports 56 and 57, the motor will stop becausethe piston will be locked by bodies of incompressible fluid, one aboveand the other below the piston. This means then, that for every positionassumed by the motor piston, the throttle valve has a correspondingposition, and admits a predetermined amount of steam or other elasticfluid to the turbine. If the speed continues to increase, the collarwill again rise, and the same action be repeated, the movement of themotor each time restoring the relay valve to its initial position, whereit shuts off the entrance and exhaust of fluid from the motor cylinder.On the other hand when the load increases and the speed falls, thecollar 37 moves downward and with it the pivot 43. Pivot 44 then acts asthe fulcrum of the lever. This will depress the pilot valve and open theport 57, communicating with the under side of the piston, to thehigh-pressure fluid and open the port 56 communicating with the upperside of the piston to the exhaust. As soon as the piston starts intomotion, the pivots 43 on the governor collar act as the fulcrum for thegovernor lever, and the pilot valve will be restored to its normalposition by the upward movement of the throttle valve and motor piston.lVhen the collar rises, it carries with it the pivot 49. As this pivotmoves upwardly, the left hand end of the lever 60 is depressed, and thehead 62 moving downwardly compresses the upper spring 64 to a greater orless extent, thus nterposing a greater opposition to the governorweights. On the other hand, when the collar moves downwardly, the pivot49 is depressed and the left hand of the lever 60 moves upwardly andfurther compresses the lower spring 65, which opposes the action on thecentrifugal weights of the governor.

It is important to have a valve which is so arranged that it has a longtravel with a gradually increasing opening, and with the seat soarranged that it will not be cut by the steam flowing through it.

In Fig. 4 is shown a type of throttle valve which I have found to besatisfactory in practice. 70 represents the valve casing having an upperconical seat 71 and a lower conical seat 7 2. Rising from the valveseats are walls 73 which flare outwardly a limited amount, and anycutting which takes place is limited to these surfaces and also to thecylindrical walls or surfaces 74 on the valve 7 5. In dotted lines isshown the position of the valve when open. The valve is provided withaxial passages to balance it and a stem 7 6.

I have shown my invention as applied only to the admission valves of aturbine, but it is to be understood that it can be applied to the stagevalves as well, and I aim to include such a use in the claims.

The invention is shown in connection with a socalled impact machine butit is to be understood that the invention can be used in connection withmachines of the reaction type or those operating by impact and reaction.The shaft of the turbine can occupy a horizontal or an upright position,as desired. Changing the position of the shaft would naturally changethe location of the various parts of the governing mechanism withouthowever, changing the principle of operation.

The construction described is well adapted for machines differinggreatly in size, which is, of course, a decided advantage in that itgreatly reduces the cost of manufacture, and simplifies the apparatus.For a great many sizes the governor, bracket, pilot valve, springs,etc., remain the same, the only diflerence being in the length of thegovernor lever. For the larger machines it is preferable to have agreater movement of the motor piston and throttle valve than for thesmall machine, and as the former are naturally larger in diameter thanthe latter, and the valves farther from the wheel axis, the increasedlength of the lever is easily and naturally obtained.

The governor is of the constant energy type so that the collar will becapable of exerting the same, or substantially the same force ateverypoint in its travel. Changing the tensions of the springs 64: and 65changes the number of revolutions per unit of time but does not changethe characteristics of the governor. With the construction shown, aturbine can readily be governed within one-half of one per cent. speedvariation due to load changes, and within two per cent. from no load tofull load.

By applying the force of the springs (is and 65 to the governor lever inthe manner described, I am enabled to use short and. relatively stifl'springs, which is an impor tant advantage. The total travel of the pivot49 is purposely made small so that its movements up and doWn will notmaterially change the tension on the adjusting springs. When thegovernor lever is in the central position and the abutment 66 midwaybetween the fixed abutments, the eilect of the springs on the governorlever will be neutral, for one opposes the other.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof;but I desire to have it understood that the apparatus shown is onlyillustrative, and that the invention can be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. In a governing mechanism for turbines, the combination of aregulating valve, a motor for operating it, a governor controlledcollar, a lever pivotally secured to a part of the motor and to thecollar and supported thereby, a controller directly connected to andmoved by the lever so that movements of the collar move the controllerfrom its normal position and the motor restores it, and a spring meansalso connected to the lever and controller and subjected to changes instress each time the controller is moved from its normal position.

2. In a governing mechanism for turbines, the combination of aregulating valve, a motor for operating it, a governor-controlledcollar, a lever pivotally secured to a part of the motor at one end andto the collar at the other, a controller for the motor located betweenthe ends of and connected to said lever, a second lever pivotallyconnected to the first, and a spring connected to the second lever whichopposes the action of the governor.

3. In a governing mechanism for turbines, the combination of a low-speedshaft, a governor driven thereby, a collar actuated by the governor, aregulating valve, a hydraulic motor for actuating the valve, a leverpivotally connected to the collar and to a part of the motor andsupported thereby, a pilot valve for the motor, a pivotal connectionbetween the motor and pilot valve, and an adjustable yielding meansacting on the governor through the lever for changing the speed of theturbine.

4. In a governing mechanism for turbines, the combination of aregulating valve, a speed governor controlling the action of the valve,and a device acting on the governor comprising opposed springs and anadjustable abutment between the springs for changing the efi'ectiveaction of the governor on the valve.

5. In a governing mechanism for turbines, the combination of aregulating valve, a speed governor controlling the action of the valve,a low-speed shaft for driving the governor, a casing for the shaft, abracket mounted on the casing, springs for adjusting the effectiveaction of the governor on the valve, an abutment mounted in the bracketand guided thereby which is situated between the springs, and ascrew-threzuled means also carried by the bracket for changing theposition of the abutment.

6. In a governing mechanism, the combination of a valve chest havingports leading therefrom, a rod passing therethrough, a valve on one endof the rod, a governor-controlled motor on the other end, and one ormore secondary regulating valves for the ports the stems of which passthrough the chest and are adapted to receive a means for actuating them.

7. In a governing mechanism, the combination of a valve chest havingports leading therefrom, a slotted rod extending therethrough, athrottle valve connected to one end of the rod and a motor at the other,one or more secondary regulators, the stems of which extend through theslot in the rod, and means for actuating the secondary regulators.

S. In a governing mechanism for turbines, the combination of a turbinecasing, a valve chest attached thereto and having outlet ports, a valveseat at the lower end of the chest, a throttle valve arranged to engagetherewith, a motor mounted on the chest for actuating the valve, and oneor more secondary regulators for controlling outlet ports of the chest,the axes of the throttle valve and secondary regulators be ing at rightangles to each other.

9. In a governing mechanism for turbines, the combination of aregulating valve, a motor for actuating it, a governor, a controller forthe motor, a support on which the controller is mounted, a leverpivotally connected to the governor and also to the controller andmotor, a spring means also carried by the support, and a lever whichconnects the spring means with the pivot that unites the governor andcontroller.

10. In a governing mechanism for turbines, the combination of aregulating valve, a motor for actuating it, a governor, a controller forthe motor, a support on which the controller is mounted, a leverpivotally connected to the governor and also to the controller andmotor, a spring means also car ried by the support, a lever whichconnects the spring means with the same pivot that unites the governorlever and controller, a link which supports the second lever, and ameans for adjusting the eifective action of the spring means.

11. In a governing mechanism for turbines, the combination of aregulating valve, a motor for actuating it, a governor, a controller forthe motor, a bracket on which the controller is mounted, a leverpivotally connected to the governor and controller, a movable abutmentcarried by the bracket, springs on each side of the abutment, a screwfor adjusting the abutment between the springs, a second lever whichtransfers the eifects of the springs to the overnor, a pivot for thesecond lever carrier? by the bracket, and a cushioning device betweenthe first lever and the controller.

12. I11 a governing mechanism, the combination of a valve casing, portsextending perpendicularly therefrom and supplying fluid-dischargingdevices, a regulating valve located at one end of the casing, a motorfor actuating the valve located at the opposite end, individual valvesfor controlling the passage of motive fluid through the ports whosestems extend through the easing, a device that connects the motor andregulating valve and extends perpendicularly to the said stems, and agovernor for controlling the action of the motor.

13. In a governing mechanism, the combination of a valve casing, portsleading therefrom, a regulating valve located at one end of the casing,a motor located at the opposite end, a slotted connector uniting thevalve and motor, individual valves controlling the passage of fluidthrough the ports, stems for the said individual valves that extendthrough the slot in the connector, a pilot valve for the motor, a speedgovernor for actuating the pilot valve, and a means for preventingovertravel of the motor.

In witness whereof, I have hereunto set my hand this 24th day ofOctober, 1906.

WALTER KIESER.

Witnesses:

ISAAC BONEPARTI-I, LE0 G. Foss.

